Automated external defibrillator drones and their role in emergency response
Authors: Sean S Scholz, Karl-Christian Thies
Journal: The Lancet Digital Health (2023)

In this issue of The Lancet Digital Health, Sofia Schierbeck and collegues1Schierbeck S Nord A Svensson L et al.Drone delivery of automated external defibrillators compared with ambulance arrival in real-life suspected out-of-hospital cardiac arrests: a prospective observational study in Sweden.Lancet Digit Health. 2023; 5: e862-e871Summary Full Text Full Text PDF Scopus (1) Google Scholar present their findings on the integration of drones equipped with automated external defibrillators (AEDs) into the chain of survival for patients with out-of-hospital cardiac arrests. Rapid bystander cardiopulmonary resuscitation (CPR) and defibrillation are essential in treating out-of-hospital cardiac arrests. For each minute that passes, the chances of survival diminish considerably.2Bækgaard JS Viereck S M⊘ller TP Ersb⊘ll AK Lippert F Folke F the effects of public access defibrillation on survival after out-of-hospital cardiac arrest: a systematic review of observational studies.Circulation. 2017; 136: 954-965Crossref PubMed Scopus (123) Google Scholar Despite their importance, AEDs are often unavailable, especially in residential areas where the majority of out-of-hospital cardiac arrest incidents occur.3Hansen SM Hansen CM Folke F et al.Bystander defibrillation for out-of-hospital cardiac arrest in public vs residential locations.JAMA Cardiol. 2017; 2: 507-514Crossref PubMed Scopus (103) Google Scholar Furthermore, a general lack of familiarity with AEDs among bystanders4Sedig K Seaton MB Drennan IR Cheskes S Dainty KN “Drones are a great idea! What is an AED?” novel insights from a qualitative study on public perception of using drones to deliver automatic external defibrillators.Resusc Plus. 2020; 4100033 Crossref PubMed Scopus (24) Google Scholar has possibly impeded the wider implementation of public-access defibrillation, leading to detrimental delays in initial defibrillation and, consequently, worsened patient outcomes. To bridge this gap, drone technology has been proposed as a transformative addition to the chain of survival. It not only provides an answer to the AED deficit but might also prove more cost-effective than traditional stationary systems,5Röper JWA Fischer K Baumgarten MC Thies KC Hahnenkamp K Fleßa S Can drones save lives and money? An economic evaluation of airborne delivery of automated external defibrillators.Eur J Health Econ. 2023; 24: 1141-1150Crossref Scopus (6) Google Scholar especially when utilised across multiple agencies.6Thies KC Jansen G Wähnert D K. AED drones on the rise? Use of drones to improve public access defibrillation.Anaesthesiologie. 2022; 71: 865-871Crossref Scopus (2) Google Scholar Several simulation studies have already demonstrated the potential of airborne AED delivery, but it was the first successful use of a drone-delivered AED in an out-of-hospital cardiac arrest7Schierbeck S Svensson L Claesson A Use of a drone-delivered automated external defibrillator in an out-of-hospital cardiac arrest.N Engl J Med. 2022; 386: 1953-1954Crossref PubMed Scopus (16) Google Scholar that gathered international media attention and also invigorated the research community. Schierbeck and colleagues’ proof-of-concept study1Schierbeck S Nord A Svensson L et al.Drone delivery of automated external defibrillators compared with ambulance arrival in real-life suspected out-of-hospital cardiac arrests: a prospective observational study in Sweden.Lancet Digit Health. 2023; 5: e862-e871Summary Full Text Full Text PDF Scopus (1) Google Scholar marked the first successful transition of AED-drone utilisation from experimental trials to real-world clinical application, bridging a gap in existing research. During the study, drones were deployed 72 times out of 211 suspected out-of-hospital cardiac arrest alerts, achieving a median time-saving of 3 min and 14 s compared with the ambulance service's arrival. This resulted in two patients being defibrillated before ambulance arrival with one patient surviving 30 days after the event. 91% of the AEDs were accurately delivered, achieving an average cruising speed of 48 km/h in median and delivering an AED within 30 m of the intended site.1Schierbeck S Nord A Svensson L et al.Drone delivery of automated external defibrillators compared with ambulance arrival in real-life suspected out-of-hospital cardiac arrests: a prospective observational study in Sweden.Lancet Digit Health. 2023; 5: e862-e871Summary Full Text Full Text PDF Scopus (1) Google Scholar Consistent with previous simulation findings, no mishaps were reported, underscoring the method's safety.8Scholz SS Wähnert D Jansen G et al.AED delivery at night—can drones do the job? A feasibility study of unmanned aerial systems to transport automated external defibrillators during night-time.Resuscitation. 2023; 185109734 Summary Full Text Full Text PDF Scopus (2) Google Scholar, 9Baumgarten MC Röper J Hahnenkamp K Thies K-C Drones delivering automated external defibrillators—integrating unmanned aerial systems into the chain of survival: a simulation study in rural Germany.Resuscitation. 2022; 172: 139-145Summary Full Text Full Text PDF PubMed Scopus (17) Google Scholar Nevertheless, the study faced several constraints: restricted operating hours of airtraffic control, operational delays in controlled airspace, the employed drone type's inability to function in all weather conditions, a low incidence of out-of-hospital cardiac arrests, an absence of comprehensive patient data, and unexplored patient heterogeneity inherent to the study's framework. Despite these challenges, Schierbeck's team have validated the concept under real-life conditions demonstrating that the technological prerequisites for airborne AED-delivery are largely fulfilled. However, there remains a need to further refine processes and technology to enable seamless incorporation into a wider emergency response framework. Possible medical use cases could also include transporting urgently needed supplies to hard-to-reach or hazardous locations, for example, haemorrhage control packs and blood products in active shooter scenarios or other major incidents. The utility of AED-drones extends beyond the purview of medical emergencies. They also present a potential asset to diverse agencies such as the fire service and the police force. In large-scale emergencies, these drones, if equipped with state-of-the-art cameras and sensors, could support real-time situational analysis, enhancing both strategic and immediate decision making. From assessing fire spread patterns to locating individuals in complex environments or evaluating potential hazards at incident sites, drones offer unparalleled vantage points. However, the integration of drones into emergency control centres is not merely a technological addition; it necessitates comprehensive operational adaptation. Although the activation mechanism for drones remains relatively straightforward, navigating the challenges intrinsic to their deployment, including potential malfunctioning, requires rigorous training for control centre personnel. Cruise velocity, while crucial, is only one facet of speed; winged vertical take-off and landing drones, complemented by optimised launch and landing procedures, have the potential to drastically reduce time-to-intervention. Improved speed must be paired with an all-weather, night-and-day reliability to ensure robust service delivery. Additionally, solid safety protocols are paramount with increasingly congested airspaces. Implementing mandatory transponder systems for all flights in unregulated airspace is vital, especially when drones and air ambulances might be deployed simultaneously. As we envisage the future, drones must be perceived as integrated components of a holistic emergency response network. Their potential to synchronise with AED registries and Citizen First Responder systems underpins this collaborative vision. The optimal response in a cardiac arrest scenario would integrate the rapid dispatch of a drone with the immediate deployment of a trained first responder, able to engage with the drone and the AED, thereby enhancing rescue efficacy. In this context, the human factor remains key. Navigating the interaction between an individual administering telephone-guided CPR and an incoming AED-drone necessitates careful consideration. Ensuring the continuity of CPR, while capitalising on the drone's capabilities, is an operational nuance that warrants further research.10Sanfridsson J Sparrevik J Hollenberg J et al.Drone delivery of an automated external defibrillator—a mixed method simulation study of bystander experience.Scand J Trauma Resusc Emerg Med. 2019; 27: 40Crossref PubMed Scopus (73) Google Scholar In conclusion, Schierbeck and colleagues’ study stands out as a pioneering clinical exploration into the feasibility of drone-assisted AED delivery. In order to exploit the full potential of drone technology, their multifunctional capabilities should also be considered when integrating drones into existing emergency frameworks. This integration necessitates technological advancements, regulatory refinements, enhanced communication strategies, bespoke training programmes, and collaborative efforts across agencies. Striking the correct equilibrium between innovation and integration, drones could become a true game-changer, not only in cardiac arrest care. We declare no competing interests. Drone delivery of automated external defibrillators compared with ambulance arrival in real-life suspected out-of-hospital cardiac arrests: a prospective observational study in SwedenAED-equipped drones dispatched in cases of suspected out-of-hospital cardiac arrests delivered AEDs before ambulance arrival in two thirds of cases, with a clinically relevant median time benefit of more than 3 min. This intervention could potentially decrease time to attachment of an AED, before ambulance arrival. Full-Text PDF Open Access